gpg in GnuPG before 1.4.2.2 does not properly verify non-detached signatures, which allows attackers to inject unsigned data via a data packet that is not associated with a control packet, which causes the check for concatenated signatures to report that the signature is valid, a different vulnerability than CVE-2006-0455.

gpgv in GnuPG before 1.4.2.1, when using unattended signature verification, returns a 0 exit code in certain cases even when the detached signature file does not carry a signature, which could cause programs that use gpgv to assume that the signature verification has succeeded. Note: this also occurs when running the equivalent command "gpg --verify".

GnuPG (GPG) 1.0.2, and other versions up to 1.2.3, creates ElGamal type 20 (sign+encrypt) keys using the same key component for encryption as for signing, which allows attackers to determine the private key from a signature.

The key validation code in GnuPG before 1.2.2 does not properly determine the validity of keys with multiple user IDs and assigns the greatest validity of the most valid user ID, which prevents GnuPG from warning the encrypting user when a user ID does not have a trusted path.